1. Field of the Invention
This invention relates to an indicator for a vehicle, and particularly relates to a technology for prospectively indicating an engine speed given after an upcoming gear shift operation.
2. Description of the Related Art
A vehicle's indicator such as an engine speed gauge (tachometer) indicates engine speeds of an internal combustion engine for automobiles. A driver thus can drive a car while recognizing an engine speed indicated by the tachometer.
Meanwhile, in a car with a manual transmission (MT car), a shift lever or the like placed adjacent to a driver's seat is operated to make a gear shift operation of a transmission. After the gear shift operation, the engine speed of the car changes in accordance with the gear ratio. If the transmission is shifted to a lower gear, the engine speed increases. On the other hand, if the transmission is shifted to an higher gear, the engine speed decreases. Similarly, in a car that has an automatic transmission (AT car), the engine speed varies with a gear shift operation if the AT car has a manual gear shift mode. Additionally, technologies for preventing over revolution from occurring with the gear shift operation are described in JP-A-Hei 10-339333, JP-A-Hei 5-248536 and JP-A-Hei 10-175461.
Conventional indicators for a vehicle, however, simply indicate the present engine speed. Thus, there is a problem that the driver cannot determine the likely engine speed after a gear shift operation of the transmission (i.e., not recognizable before the gear shift operation).
In addition, an engine has its own engine speed range for good fuel economy and engine speed range in which a high output/high torque operation is provided. Therefore, if the gear shift operation is made under the condition that the engine speed given after the gear shift operation is not prospectively recognized, the engine speed after the gear shift operation may be largely off from the optimum engine speed ranges for fuel economy and for high output/high torque operation contrary to the intent of the driver. As a result, there arises another problem that drivability is adversely affected.